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Hold Your Breath When Visiting These Heavily Polluted Cities

Don't huff and puff when you head into these smog-ridden cities.

Car exhaust makes you cough, but pollution in these five cities can kill you. With the world's worst air quality around, here are the five cities that will literally take your breath away .

5. Quetta, Pakistan

Source: Wikimedia Commons, Pd1 uob

Fine Particulate Matter (Air Pollution) Rating

251

Population

565,000

Source: World Health Organization, United Nations

Known as the "Fruit Garden of Pakistan" due to its diverse wildlife, the country's sixth most populous city perches at a precarious elevation of 5,500 feet. But the fruit garden is going rotten, due to heightened construction and unregulated smoke pollution from cars and factories .

The Lonely Planet guidebook calls it a "frontier town," which explains both the air-killing exhaust emissions , as well as why pollution isn't such a problem for those passing through . Thankfully, Quetta has found a far-away ally in The Netherlands, who are funding a six-year project to put the city and its fruit garden back on the pollution-free path.

4. Ludhiana, India

Source: Wikimedia Commons, Sunnysingh211

Fine Particulate Matter (Air Pollution) Rating

251

Population

1,400,000

Source: World Health Organization, United Nations

Tied with Quetta for particulate matter, this Indian metropolis is a mess. Ludhiana has more vehicles and factories than any other city in its northern Punjab district – but that's nothing to brag about. Not only does particulate matter put Ludhianans at higher risk of lung cancer , the city's water is filled with toxic sludge and noise pollution in some areas reaches 104 decibels – enough to cause fetus damage – according to the Hindustan Times .

Sanandaj hugs the border of Iraq, but Iraq most likely doesn't want to hug back. Four Iranian cities made the top ten list of most polluted cities, and Sanandaj's third place finish is nearly the worst of them.

As with India, there's a lot of finger pointing and little action. The Iranian government has blamed the United States, alleging that toxic dust from uranium bombs dropped during the Iraq War is the primary purpose for its country's plentiful pollution . The Tehran Times chooses to pick its fights closer to home, noting that "[d]ust, mostly originating from Iraq, is one of the prime factors behind the pollution in these Iranian cities ."

2. Ulaanbaatar, Mongolia

Source: Flickr, Anthony Knuppel

Fine Particulate Matter (Air Pollution) Rating

279

Population

1,132,000

Source: World Health Organization, United Nations

Mongolia's capital is a convoluted mix of city and country. With high rises at its center and "ger" areas (nomadic tent slums) around its edges, Ulaanbaatar's pollution originates from everything from power plants to stove ash .

"Today, children are suffering from many unfamiliar illnesses caused by air pollution," said a local resident to the World Bank. "As a mother I am very worried about my children's health and my neighbors' newborns," Gerelchimeg says. "I don't want my children to be sick only because they are living in ger areas ."

When households heat up stoves during winter, the pollution problem becomes a pandemic. Ger heating accounts for a whopping 60% to 70% of winter pollution . At a conservative guess, researchers estimate that air pollution causes one in every 10 deaths in the city .

1. Ahwaz, Iran

Source: Wikimedia Commons, National Iranian Oil Company

Fine Particulate Matter (Air Pollution) Rating

372

Population

1,430,000

Source: World Health Organization, United Nations

When it rains in Ahwaz, it pours. As the most polluted city in the world, raindrops don't wash away the grime – they carry acid. When the first drops of the wet season hit southern Iran last November, almost 6,000 people headed to hospitals complaining of shortness of breath .

In a statement to Khabar Online, the President of Ahwaz University Medical and Health Services said, "It is my guess and estimation that chemical materials from the factories in Khuzestan and their runoff during the rain could be a factor in this incident, but right now we really don't know what caused this and we cannot give exact opinions ."

But things aren't much better during the dry season-massive dust storms carry pollution into town from as far away as Turkey ,

The British Ahwazi Friendship Society blames river diversion, marsh draining, and various processing plants, while the United Nations Environment Programme has warned are causing "irreversible ecological destruction ."